Elucidating the Chirality-Induced Spin Selectivity Effect of Co-Doped NiO Deposited on Ni Foam for Highly Stable Zn–Air Batteries

The urgent need to alleviate global warming and limit the consumption of fossil fuels has prompted the development of rechargeable Zn-air batteries (ZABs) considering their superior energy density, safety, and cost-effectiveness. However, the sluggish reaction kinetics of the oxygen evolution reaction (OER) and the unfavorable properties of conventional OER catalysts (including low electrical conductivity and the use of active site-blocking binders) hinder the development of practically viable ZABs. Herein, we report a distinct approach for directly synthesizing cobalt-doped nickel oxide (Co-NiO) with a chiral structure on porous Ni foam via a one-step hydrothermal process. The chirality-induced spin selectivity (CISS) boosts the OER kinetics, while Co doping elevates the electrical conductivity and the abundance of active sites on the catalyst. The chiral Co-NiO demonstrates an OER current density of 10 mA cm^-2 at 1.58 V versus the reversible hydrogen electrode, outperforming both achiral Co-NiO and undoped NiO. Furthermore, a chiral Co-NiO-based rechargeable ZAB demonstrates a high open-circuit potential (1.57 V), a low charge/discharge overpotential (0.71 V), and excellent stability for 960 h (40 days) because the CISS effect mitigates the production of the corrosive singlet oxygen. These results represent a prominent pathway for the advancement of ZABs using the low-cost oxygen evolution catalyst modulated by the CISS effect and heteroatomic doping.